HUNTINGTON, Utah -- Detection of a noise in the Utah coal mine where six miners have been trapped nine days led rescuers to pick a new spot for a bore hole that might reach them.

However, Richard Stickler of the U.S. Mine Safety and Health Administration cautioned "don't read too much into" the fact a sound had been heard inside the mine.

He said officials also were influenced by a determination that the new drill location was over an area of the mine they now think would have provided the men a better chance of building protective barriers if they were able to try to save themselves.

Video cameras and microphones put down the first three holes failed to produce any sign of the miners alive or dead.

Meanwhile, efforts to reopen the main tunnel to the area where the miners are trapped continued to be slowed by ongoing seismic "bumps" that bring down more rubble and make it unsafe for rescuers digging their way to the men.